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mysql CPU usage too high

harivaag
Hi All, my cpu load is always high and my LA is between 1 to 4 I want to optimize the same for performance, coz 4 months back, i had about 100+ visitors real time on my website with a traffic of 15000+ per day and now i just have about 30 - 40 visitors and also the website goes down at times for some time and i have to restart mysql. I have multiple Databases and making use of max myisam and min of innodb tables Any help would be appreciated please My server config as below HP DL 120 G7, Single Proc Quad Core - Intel Xeon E1220 (1 CPU x 4 Cores) - 500 GB x 2 SATA Hard Disks on Raid 1 - 16 GB DDRII ECC Registered RAM my.cnf as below [mysqld] local-infile=0 skip-name-resolve max_connections=600 low_priority_updates=1 myisam-recover=backup,force thread_concurrency=8 concurrent_insert=2 thread_cache_size=48 max_allowed_packet=8M innodb_buffer_pool_size=512M innodb_additional_mem_pool_size=10M innodb_flush_method=O_DIRECT symbolic-links=0 socket=/var/lib/mysql/mysql.sock interactive_timeout = 100 connect_timeout = 60 wait_timeout = 120 tmp_table_size = 256M max_heap_table_size = 256M join_buffer_size=2M read_buffer_size=4M sort_buffer_size=2M table_open_cache=1024 read_rnd_buffer_size=2M key_buffer =2G max_allowed_packet=8M max_connect_errors=10 myisam_sort_buffer_size=64M query_cache_limit=3M query_cache_size=1G query_cache_type=1 open_files_limit=4466 [mysqldump] quick max_allowed_packet=16M [mysql] no-auto-rehash [isamchk] key_buffer=128M sort_buffer=128M read_buffer=4M write_buffer=2M [myisamchk] key_buffer_size = 128M sort_buffer_size = 128M read_buffer = 4M write_buffer = 2M
================= mysqlunner resutls ----------------- -------- General Statistics ----------------------------------------- --------- [--] Skipped version check for MySQLTuner script [OK] Currently running supported MySQL version 5.1.70-cll [OK] Operating on 64-bit architecture -------- Storage Engine Statistics ---------------------------------- --------- [--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster [--] Data in MyISAM tables: 2G (Tables: 676) [--] Data in InnoDB tables: 137M (Tables: 85) [!!] Total fragmented tables: 98 -------- Security Recommendations ---------------------------------- --------- [OK] All database users have passwords assigned -------- Performance Metrics ---------------------------------------- --------- [--] Up for: 6h 16m 36s (5M q [246.189 qps], 28K conn, TX: 8B, RX: 1B ) [--] Reads / Writes: 83% / 17% [--] Total buffers: 3.8G global + 10.2M per thread (600 max threads) [OK] Maximum possible memory usage: 9.8G (62% of installed RAM) [OK] Slow queries: 0% (60/5M) [OK] Highest usage of available connections: 5% (35/600) [OK] Key buffer size / total MyISAM indexes: 2.0G/1.1G [OK] Key buffer hit rate: 100.0% (749M cached / 39K reads) [OK] Query cache efficiency: 84.1% (4M cached / 5M selects) [OK] Query cache prunes per day: 0 [OK] Sorts requiring temporary tables: 0% (0 temp sorts / 79K sorts) [!!] Joins performed without indexes: 455 [!!] Temporary tables created on disk: 29% (29K on disk / 100K total) [OK] Thread cache hit rate: 99% (35 created / 28K connections) [OK] Table cache hit rate: 98% (460 open / 467 opened) [OK] Open file limit used: 13% (610/4K) [OK] Table locks acquired immediately: 99% (1M immediate / 1M locks) [OK] InnoDB data size / buffer pool: 137.7M/512.0M -------- Recommendations -------------------------------------------- --------- General recommendations: Run OPTIMIZE TABLE to defragment tables for better performance MySQL started within last 24 hours - recommendations may be inacc urate Enable the slow query log to troubleshoot bad queries Adjust your join queries to always utilize indexes Temporary table size is already large - reduce result set size Reduce your SELECT DISTINCT queries without LIMIT clauses Variables to adjust: join_buffer_size (> 2.0M, or always use indexes with joins) ================== tuning-primer.sh results as below ------------------------------- SLOW QUERIES The slow query log is NOT enabled. Current long_query_time = 10.000000 sec. You have 60 out of 5611712 that take longer than 10.000000 sec. to complete Your long_query_time seems to be fine BINARY UPDATE LOG The binary update log is NOT enabled. You will not be able to do point in time recovery See [url=http://dev.mysql.com/doc/refman/5.1/en/point-in-time-recovery.html]MySQL :: MySQL 5.1 Reference Manual :: 7.5 Point-in-Time (Incremental) Recovery Using the Binary Log WORKER THREADS Current thread_cache_size = 48 Current threads_cached = 30 Current threads_per_sec = 0 Historic threads_per_sec = 0 Your thread_cache_size is fine MAX CONNECTIONS Current max_connections = 600 Current threads_connected = 4 Historic max_used_connections = 35 The number of used connections is 5% of the configured maximum. You are using less than 10% of your configured max_connections. Lowering max_connections could help to avoid an over-allocation of memory See "MEMORY USAGE" section to make sure you are not over-allocating INNODB STATUS Current InnoDB index space = 22 M Current InnoDB data space = 137 M Current InnoDB buffer pool free = 92 % Current innodb_buffer_pool_size = 512 M Depending on how much space your innodb indexes take up it may be safe to increase this value to up to 2 / 3 of total system memory MEMORY USAGE Max Memory Ever Allocated : 3.86 G Configured Max Per-thread Buffers : 6.00 G Configured Max Global Buffers : 3.51 G Configured Max Memory Limit : 9.51 G Physical Memory : 15.64 G Max memory limit seem to be within acceptable norms KEY BUFFER Current MyISAM index space = 1.12 G Current key_buffer_size = 2.00 G Key cache miss rate is 1 : 18978 Key buffer free ratio = 79 % Your key_buffer_size seems to be too high. Perhaps you can use these resources elsewhere QUERY CACHE Query cache is enabled Current query_cache_size = 1.00 G Current query_cache_used = 606 M Current query_cache_limit = 3 M Current Query cache Memory fill ratio = 59.25 % Current query_cache_min_res_unit = 4 K MySQL won't cache query results that are larger than query_cache_limit in size SORT OPERATIONS Current sort_buffer_size = 2 M Current read_rnd_buffer_size = 2 M Sort buffer seems to be fine JOINS Current join_buffer_size = 2.00 M You have had 76 queries where a join could not use an index properly You have had 379 joins without keys that check for key usage after each row You should enable "log-queries-not-using-indexes" Then look for non indexed joins in the slow query log. If you are unable to optimize your queries you may want to increase your join_buffer_size to accommodate larger joins in one pass. Note! This script will still suggest raising the join_buffer_size when ANY joins not using indexes are found. OPEN FILES LIMIT Current open_files_limit = 4466 files The open_files_limit should typically be set to at least 2x-3x that of table_cache if you have heavy MyISAM usage. Your open_files_limit value seems to be fine TABLE CACHE Current table_open_cache = 1024 tables Current table_definition_cache = 256 tables You have a total of 784 tables You have 1024 open tables. Current table_cache hit rate is 95% , while 100% of your table cache is in use You should probably increase your table_cache You should probably increase your table_definition_cache value. TEMP TABLES Current max_heap_table_size = 256 M Current tmp_table_size = 256 M Of 71818 temp tables, 29% were created on disk Perhaps you should increase your tmp_table_size and/or max_heap_table_size to reduce the number of disk-based temporary tables Note! BLOB and TEXT columns are not allow in memory tables. If you are using these columns raising these values might not impact your ratio of on disk temp tables. TABLE SCANS Current read_buffer_size = 4 M Current table scan ratio = 448 : 1 read_buffer_size seems to be fine TABLE LOCKING Current Lock Wait ratio = 1 : 2558 You may benefit from selective use of InnoDB. ======================

Comments

6 comments

Date Votes
  • thinkbot
    adjust: tmp_table_size = 50M max_heap_table_size = 50M join_buffer_size=1M read_buffer_size=128K sort_buffer_size=2M read_rnd_buffer_size=256K table_open_cache=1024 query_cache_size=100M myisam_sort_buffer_size=512M slow_query_log=1 slow_query_log_file=mysql-slow.log long_query_time=0.1 - what script do you use ? custom or CMS ? with some third party plugins ? - it would be good to review your slow queries, since [!!] Temporary tables created on disk: 29% (29K on disk / 100K total)
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  • harivaag
    HI, Thanks, have applied the same and will check for the day today... [COLOR="silver">- - - Updated - - - hi sorry forgot to answer your questions, we use X-cart for the website and use custom build php based CMS
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  • harivaag
    Hi, After making the changes and checking for a day, just now the LA just went up to 80% and then i had to restart.... Kindly help me to resolve the same
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  • thinkbot
    what do you mean by LA and where do you check it ? please review slow queries, like that : cd /root/install wget
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  • harivaag
    Thanks, LA means Load Average on the PUTTY I will put the slow.txt soon
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  • cPanelMichael
    Hello :) Please note that additional information on troubleshooting the server load (aside from MySQL usage) is available at: Troubleshooting High Load On Linux Systems Thank you.
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